Field
The present disclosure relates generally to a broadcast receiver and a control method thereof, and for example, to a broadcast receiver, in which antenna connection is automatically determined, and a control method thereof.
Description of Related Art
Antenna connection is essential to search a channel during an initial setting process of a broadcast receiver and store information about the searched channel. If the antenna connection is not achieved, it is impossible to receive broadcast information and thus impossible to search a channel. Therefore, there is a need of checking whether the antenna is connected to the broadcast receiver so as to search broadcast channels.
However, a conventional broadcast receiver does not automatically determine whether the antenna is connected to the broadcast receiver, and directly receives a user's input about whether the antenna is connected or not before starting a broadcast channel search.
FIG. 1 is a flowchart illustrating an example of a conventional initial setting process of a television (TV). In case of the conventional initial setting process of the TV, a user has to set a language and a country (S101), and select whether an input signal to be received in the TV is a broadcast signal transmitted from an antenna or a signal from a high definition multimedia interface (HDMI) (S102). After a user's input that the antenna is connected to the TV (that is, the input signal is the broadcast signal), a channel auto-scan (i.e. auto program) starts (S103). Therefore, the initial setting process is delayed as much as a user's input and thus inconvenient for a user.
The reasons why the conventional broadcast receiver directly receives a user's input without automatically determining whether an antenna cable is connected thereto or not are because there were no techniques for sufficiently quickly measuring the strength of the signal input to the broadcast receiver and there were no efficient methods of accurately determining whether the antenna cable is connected or not based on the strength of the broadcast signal even though the strength of the received broadcast signal was measured.
FIG. 2 is a diagram illustrating an example of a conventional technique for measuring a received signal strength indicator (RSSI) of a signal input to the broadcast receiver. In such a conventional case, the RSSI is calculated by the following [Formula 1].
                    RSSI        =                              1            N                    ⁢                                    ∑                              k                =                0                                            N                -                1                                      ⁢                                                  ⁢                          (                                                I                  k                  2                                +                                  Q                  k                  2                                            )                                                          [                  Formula          ⁢                                          ⁢          1                ]            
That is, an I channel signal I(t) and a Q channel signal Q(t) received through an antenna 210 are respectively converted into corresponding digital signals Ik and Qk by I and Q channel analog digital converters (ADC) 220 and 230, and then respectively squared by I and Q channel squarers 240 and 250. After that, the respective squared values are accumulated by an accumulator and dumper 260, and the accumulated values are finally averaged by an averager 270, thereby measuring the RSSI.
Like this, complicated processes were needed to conventionally measure the strength of the signal input to the broadcast receiver, i.e. the RSSI. To this end, complexity of hardware was also increased, and it took long time to measure the RSSI. Therefore, there was no effectiveness even though the broadcast receiver automatically determines whether the antenna is connected or not. To automatically determine whether the antenna is connected or not, the strength of the signal input to the broadcast receiver has to be measured according to broadcast frequencies, and the antenna connection has to be determined by a specific method based on the strength of the input signal. If it takes long time to measure the strength of the signal input to the broadcast receiver according to the broadcast frequencies, the automatic determination about the antenna connection is not more advantageous than a user's determination in light of time.
Further, there were no efficient conventional methods of accurately determining whether the antenna cable is connected or not based on the strength of the received broadcast signal even though the strength of the received broadcast signal is measured. The most basic method of automatically determining the antenna connection is that the strength of the signal input to the broadcast receiver is first measured according to the broadcast frequencies and it is then determined that the antenna cable is connected when anyone of the measured values is greater than a certain reference value. In this case, if the reference value is too high, it is determined that the antenna is not connected even though the antenna is actually connected since the strength of the received signal does not exceed the reference value. On the other hand, if the reference value is too low, it is determined that the antenna is connected even though the antenna is not actually connected since the strength of the signal received with noise exceeds the reference value. Accordingly, determination results are inaccurately obtained.